Question: $ { \left[\begin{array}{rrr}{3} & {0} & {0} \\ {0} & {-1} & {3}\end{array}\right]-\left[\begin{array}{rrr}{2} & {0} & {4} \\ {3} & {1} & {0}\end{array}\right] = {?} } $
Answer: To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rrr}{3}-{2} & {0}-{0} & {0}-{4} \\ {0}-{3} & {-1}-{1} & {3}-{0}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{1} & {0} & {-4} \\ {-3} & {-2} & {3}\end{array}\right]}$